The average maximum temperature during January 2015 was 8.3 Celsius (47F), and that was just 0.1 Celsius (0.2F) above normal. The average minimum temperature was 2.8 Celsius (37F), and that was 0.5 Celsius (1F) below the monthly normal.

The highest temperature recorded during January was 15.0 Celsius (59F) on the 9th. This was the highest January temperature for 12 years. There were 6 other days when maxima exceeded 10 Celsius (50F), but only 2 of these milder days had highs above 11 Celsius (52F). Most of the milder days occurred before the 13th, with the exception of the 26th and 28th, when maxima were a fraction over 10 Celsius (50F). The colder weather was mostly confined to the second half of the month, with 3 of the 4 days with maxima below 5 Celsius (41F) occurring after the 17th. However, the coldest day of the month was the 4th, when the temperature only reached 2.5 Celsius (37F).

There was only 1 very mild night during the month and that was the 9th/10th, when a minimum temperature of 12.1 Celsius (54F) was recorded. This was the mildest January night for 7 years. The second mildest night was the 7th/8th, with a low of 8.6 Celsius (48F), but there 6 other nights when the temperature failed to drop below 7 Celsius (45F). The coldest nights were mainly during the second half of the month. On 17 nights the temperature fell below 3 Celsius (37F), but only 4 of these colder nights occurred before mid month. Each night between the 17th and 25th (9 nights) had minima below 3 Celsius (37F). There were 2 very cold nights. The 19th/20th and 22nd/23rd both had minima below minus 5 Celsius (23F), with the latter night fractionally the coldest at minus 5.6 Celsius (22F).

Frost

There were 9 air frosts during January, and that's 2 above the average. Only 2 air frosts occurred before mid month, and these were slight with minima of minus 1.5 Celsius (30F) and minus 1.6 Celsius (29F) on the 3rd/4th and 6th/7th respectively. Of the remaining 7 air frosts, 3 were slight, with minima above minus 2 Celsius (28F). The other 4 air frosts all occurred in the period between the 16th/17th and the 22nd/23rd. There were 14 grass frosts during the month, and all bar 3 of them were after mid month. Between the 16th/17th and the end of the month there were only 4 grass frost free nights. There were 5 nights when grass temperatures fell to minus 5 Celsius (23F) or lower, with 2 of these nights coinciding with the only early in the month air frosts. On the 2 coldest nights of the month, the 19th/20th and 22nd/23rd, grass temperatures fell to minus 7.4 Celsius (19F) and minus 9.9 Celsius (14F) respectively.

Rain

A total of 64.5 millimetres (2.5 ins.) of rain fell during January, and this was less than 10% above the long-term average. There were 19 days with significant* rain and this was 2 above average, and there were 14 wet** days during January and that was 3 days above average for the month. There were only 6 completely dry days during the month, and there were a further 5 days when just a trace of rain was measured. There was rain on the first day of the New Year and over 10 millimetres (0.4 ins) fell on the 2nd. On both the 7th and 8th there were falls of over 5 millimetres (0.2 ins), but the wettest day was the 12th, when 12.0 millimetres (0.5 ins) was recorded. There was a further fall above 5 millimetres (0.2 ins) on the 14th, but during the second half of the month rainfall was generally lighter with more in the way of dry weather. On both the 23rd and 31st rainfall exceeded 3 millimetres (0.1 ins), but by way of contrast, the second half of January only had 13.8 millimetres (0.54 ins) of rain, accounting for just over 20% of the monthly total.

*Significant rain is defined as one that has 0.2mm or more. ** A wet day is defined as one that has 1mm, or more, of rain

Thunderstorms

There were no thunderstorms observed in Morden during January.

Hail

There was soft hail observed in a a shower on the afternoon of the 29th.

Snow

There were 2 days of snow during January, 1 below average. On the 29th there was a sleet and snow shower late in the afternoon, and light snow was also observed mid evening. Sleet and wet snow fell on the morning of the 31st and snow lay for a while on the grass, garden and cars with some slush on the roofs. All snow had thawed by early afternoon.

Wind

The winds during January were predominantly from the southwest, and accounted for over half the daily recorded directions. Winds were less persistently from the southwest during the third week but there were no days when northeasterly winds were observed. The last time northeasterly winds were absent during January was 8 years ago. Winds were fairly strong at times during the first fortnight, but after a lull during the third week, when light or gentle winds prevailed, stronger winds returned at the end of the month. There were 17 days when gusts exceeded 20 knots (23 mph) with only 5 of these windier days occurring after mid month. On 7 days, gusts reached, or exceeded, 30 knots (34 mph), but the only very windy day after mid month was the 28th, when a gust of 35 knots (40 mph) was recorded. There was a gust of 34 knots (39 mph) on the 10th, but the windiest day of the month was the 15th, when 44 knots (50 mph) was measured.